The confidential EU document from last year was made public by two Belgian opposition parties. It said oversight of security at the nation's airports was flawed and cited serious deficiencies in the way safety checks are managed.

The revelations came after the March 22 attacks in Brussels killed 32 people, including 16 at the national airport. The Islamic State group has claimed responsibility.

Ms Galant had said she had not seen the EU report, but Mr Michel said "a summary of this report was discussed and sent to the minister's cabinet in June 2015".

No immediate replacement was named but Mr Michel said he would do so as soon as possible.

The suicide attacks in the peak morning travel period have shaken the Belgian government, police and judiciary.

Parliament has set up an inquiry to look into any shortcomings in the handling of the bombings. The interior and justice ministers volunteered to step down last month, but their resignations were rejected.

"The government will work in perfect co-operation with the commission of inquiry so that all transparency can be ensured and to draw lessons for the future," Mr Michel said. "The security of all Belgians is a priority for this government."

The EU carries out around 35 safety inspections at European airports each year. The restricted report, dated April 28 last year, details shortcomings in the supervision of security in the Brussels Airport section that travellers enter once they have cleared security checks and around the planes themselves.

The suicide bombers blew themselves up in the departure area of Belgium's main international airport, part of the facility that was not covered in the EU report.

At a hastily organised press conference, Ms Galant rejected allegations that she had been lax about security.

"If there's an area I always paid attention to it's that one," she said.

She told reporters she was the victim of a "media crusade" organised by a senior transport official whose attacks on her would not end until she resigned.

Ms Galant accused her foes of "riding the current wave of worry" provoked by the Brussels attacks.